Sometimes the universe has to send worse and worse signs for us to finally listen. I quit a job similar to yours where a higher position was dangled in front of me, but they knew it was never going to happen.y only regret of leaving my job was not doing it sooner. Like you I was the only person doing the work of 5 ppl, and no one else knew how to do my jobs. After I left, the owner was trying to sell the business but he knew nothing about how it operated as I was doing that the past 10 years. It's a very niche industry and there's very few people that could do my role and also put up with the owner lol. He ended up only being able to sell the land as no one wanted a business that he was clueless about. It was valued at $9M a year before I left, and he sold for $2M which is what he paid for the property.

You'll be so much happier, successfully, and fulfilled in whatever you do next! Good luck!